Telephony.



M. L. JOHNSON.

TELEPHONY.

APPLICATION FILED FEB. 24. I913. 1,185,331. Patented May-30;1916.

5 SHEETS-SHEET I I W ITNEE SES @32 5 7/0022. MORTON. L JOHNSON.

ATTORNEY M. L. JOHNSON.

TELEPHONY.

APPLICATION FILED FEB. 24. I913.

Patented, May 30, 1916.

5 SHEETS-SHEET 2.

WITNESSES F IG. 2 NVENTQR MORTON L. JOHNSon ATTORNEY @Q/KWM M. L.JOHNSON.

TELEPHONY. APPLICATION FILED FEB- 24. 19,3- 1 ,1 85,33 1 Patented May30, 1916.

5 SHE ETS-SHEET 3.

FIG. 3

ITNESSES INVENT 0R Mqa'ron L JOHNSON.

' ATTORNEY M. L. JOHNSON.

TELEPHONY.

APPLICATION FILED FEB. 24. 1913.

1 ,1 85,33 1 I V I Patented May 30, 1916.

FIGA

VVITNESSES INVENTOR l IoRTonLJohnson e V ATTORNEY M. L. JOHNSON.

TELEPHONY.

APPLICATION FILED FEB. 24. 1913.

m w w wt w mm mm 4 W W. 5 A w m m n w m M 1 S/L 00 SJ. 5 E x 8 N .I. T 1fi m ATTORNEY s'rA'rs AT MORTON L. JOHNSON, OF CHICAGO, ILLINOIS,ASSIGNOR, BY MESNE ASSIGNMENTS, TO FRANK COOK COMPANY, OF CHICAGO,ILLINOIS, A CORPORATION OF ILLINOIS.

TELEPHONY.

Specification of Letters Patent.

Patented May 30, 1916.

Application filed February 24, 1913. Serial No. 750,286.

To all whom it may concern:

Be it known that I, MORTON L. JOHNSON, citizen of the United States,residing at Chicago, in the county of Cook and State of Illinois, haveinvented a certain new and useful Improvement in Telephony, of which thefollowing is a full, clear, concise, and exact description, referencebeing had to the accompanying drawings, forming a part of thisspecification.

The invention relates to telephone systems and contemplates meanswhereby the designations of lines with which calling subscribers desireconnection may be automatically recorded by the calling subscribers andmeans for imparting this recorded information to operators who are toestablish connections between calling and desired lines.

.\I invention has for a specific purpose the provision of a telephoneexchange system having the features above outlined and which includesmeans whereby receiving, or A operators, may enable the switching, or Boperators, to receive the recorded information, the A operators therebybeing reliered of the duty of conveying-this information to the Boperators.

By means of my invention the speed of traflic of telephone exchangesystems may be increased since the receiving or A operators need notwait to hear the number of the lines desired by calling subscribers, itbeing sufficient by means of my invention, to have the A operatorsinformed of the prefixes only of the numbers so that the A operatorswill at once extend the calling lines into connection with the Boperators that have access to the desired lines, the B operatorsreceiving their information automatically and independently of theA'operators and which inforuultion, in accordance with the preferredembodiment of the invention, may be in the process of being recordedduring the time the A operators are extending the calling lines to the Boperators positions.

By means of my invention the delay hitherto involved in establishingtelephonic communication between the A and B operators and the delayconsequent upon imparting the complete information to the A operators bythe calling subscribers and the rei'mparting of this information to theB operators by the A operators are avoided.

In a connection which is being established the speech recording andreproducing apparatus is coupled with the link that is belng handled bythe second or connecting operator so that when this operator hears therecord that informs her of the number of the desired line she willemploy the link coupled with the talking device and effect itsconnection with the desired line so that she need not be informed by thefirst or re ceiving operator either of the number of the calling line orthe number of the link to be employed.

I will explain my invention more fully by reference to the accompanyingdrawings in which Figure 1 diagrammatically indicates the telephoneexchange system arranged in accordance with the invention, circuitdetails being omitted to make this diagramclear; and Figs. 2 to 5,inclusive, taken collectively in their numerical order with theconductors at the right and left hand sides of the sheets in alinement,illustrate the telephone exchange system equipped in accordance with thepreferred embodiment of the invention.

Like parts are indicated by similar characters of reference throughoutthe different figures.

Telephone lines extend from substations to the A and B operatorspositions at the exchange or exchanges, each telephone line desirablyhaving multiple jacks in the presence of both operators when thetelephone lines extend to the same exchange building. I have indicatedsubstations 200, 201, .300, 301 extending to the exchange, thesetelephone lines having jacks 3 at the A operators positions and jacks 4at the B operators positions, the jacks 3 at the A operators positionsenabling the A operators to establish connection with desired lineswhose jacks appear before the A operators positions if such method ofconnection should be desired at any time. The jacks 4 are employed bythe B operators in the usual manner where the A and B operatorscooperate by calling subscribers automatically to extend calling linesinto connection with the link connectors E. The selector switches C areshown as being individual to the lines but the system is not to belimited to such individuality, Speech recording and reproducing devicesF are adapted for automatic association with selected link connectors E,the. selector switches C setting selector switches G into operation toconnect idle devices F with selected links E. When a call is initiated aswitch C is set into operation to select an idle link connector E and anidle switch G is set into operation to associate an idle speechrecording and reproducing device F with the selected link connector Eand thereby with the calling line. It is apparent that other means maybe employed for extending the calling lines into connection with linkconnectors E than the-selector switches C. The selected A operatorstelephone set H is preferably in stantly included in circuit with thecalling line and the A operator inquires of the calling subscriber thenumber of the desired line. The calling subscriber will speak the numberof the desired line into his telephone transmitter and the speech willbe recorded in the device F that has been brought into telephonicrelation with the calling line. The A operator, will care only to hear,at her telephone H, the prefix of the number of the desired line andwill proceed to connect the selected link connector E with a B operatorlocated at the exchange or position to which the desired line extends.The link connectors E are illustrated as being provided with connectingplugs 5, and trunk lines I intervening between the A and B operatorspositions are illustrated as being provided with trunk jacks 6 forreceiving the plugs 5. The trunk lines or link connector sections I areprovided with selector switches K whose wipers are individual to thetrunk lines and which wipers are provided with waiting contactsindividual to link connectors L extending to different B operatorspositions before which jacks of. the desired lines appear. As soon asthe A operator has heard the prefix of the desired line she will insertthe plug 5 of the selected link connector into the jack 6 pertaining tothe operators position or set of operators positions to which have beenassigned a group of telephone lines that includes the desired line (thetelephone lines being divided into groups assigned to differentswitching operators positions or sets of such positions) and willthereby cause the switch K to seek an idle link connector L. B When theswitch K has found an idle link connector L the B operator thusautomatically selected may, when responding to the signal conveyed toher (if such signal be provided, though manually operated listening keysin the operators telephone equipments may be dispensed with), set thetalking device F into operation and will listen to the designation ofthe wanted line. as furnished by the talking device and will thereaftertest the desired line and complete the connection if the desired line isidle. The B operators are provided with connecting plugs 7 and whenthese connecting plugs are inserted in the jacks of desired lines theselected talking device F is cut out of circuit and restored to itsnormal idle condition. If the desired line is busy the selected Boperator will insert the plug 7 in abusy back ack 8 similarly to restorethe previously employed talking device F to normal, the busy back jack 8also conveying a busy signal to the calling subscriber who will restorehis telephone receiver upon its switch hook, thereby to convey adisconnect signal to the A operator who will take down the connection ather position and restore the selected switch equipment C of the callingline to normal.

By means of the telephone exchange system above generally described thecalling subscriber is enabled to hear the record he has made while theswitching or connecting operator at the selected B position is listen-Thus neither operator ing to such record. need repeat the number of thedesired line to the calling subscriber. The link connector which the Aoperator connects with the B operators position to which is assigned thegroup of lines having the desired line is preferably employed forconveying the reproduced speech and while the speech record ispreferably made by the calling subscriber the invention is not to b lmited to this characteristie.

Referring now more particularly to Figs. 2 to 5, inclusive, takencollectively and in numerical order, I have there illustrated atelephone exchange system equipped in accordance with the preferredembodiment of the invention. The substations of which stations 200 and201 are diagrammatically illustrated, are provided with the usualsubstation equipment including a telephone switch hook 9, a telephonereceiver 10, av telephone transmitter 11, a call bell 12 and a condenser13, the switch hook having a normal contact .for establishing the bridgeacross the telephone line that includes the bell and con- .denser and analternate contact for establishin a bridge across the telephone linethat includes the telephone receiver and transmitter. When a subscriberinitiates a call a circuit is established traceablefrom the groundedbattery 14, the upper winding of relay 15, the uppermost armature switchof relay 16 and its normal contact, the upper armature switch of relay17 and its normal contact, both sides of the calling line, the lowerarmature switch of relay 17 and its normal contact, the intermediatearmature switch of relay 16 and its normal contact, the lower winding ofrelay 15, to ground. One circuit thereupon established is traceable fromthe grounded lower armature switch of relay 15, the contact of thisswitch, the motor magnet 18, the sluggishly operating interrupter relay19, the side switch wiper 20 in its first position, to the groundedbattery 14. The rotary magnet 18 thereupon sets the wipers 21, 22, 23,and 24 into operation until the wiper 22 engages an ungrounded waitingcontact whereupon the circuit of the private magnet 25, which circuitwas established upon the initial energization of the motor magnet 18, isopened to bring the side switch wipers 20, 26 and 27 into their secondand final positions, the wiper 20 in its second position opening thecircuit of the motor magnet 18 thereby to bring the wipers 20, 22, 23and 24 to rest.

The side switch wiper 20 in its second position closes a circuittraceable from the grounded battery 14, said side switch wiper 20 in itssecond position, the relay 16, the uppermost armature switch of theenergized sluggishly operating relay 28, to ground.

\Vhen the relay 16 is energized the circuit of o the relay 15 is openedat the normal contacts of the two upper armature switches of relay 16whereby the circuit of the sluggishly operating relay 28 is opened atthe upper armature switch of relay 15, the relay 28 then releasing itsarmature to remove ground from the relay 16, this ground being at thistime replaced at another portion of the equipment. When the relay 16 isenergized the wipers 21 and 24 are connected with the sides of thecalling line by way of the alternate contacts of the two upper armatureswitches of relay 16. The relay 29 is now placed in bridge of thecalling line by way of the armature switches of relay 30 and theirnormal contacts, the intermediate armature switches of the relay 31 andtheir contacts and the contacts engaged by the wipers 21 and 24, therelay 29 thus being energized. \Vhen the upper armature switch of thisrelay 29 is operated upon the energization of the relay, the contacts 32are momentarily engaged, being again in separated relation when thearmature switch is fully attracted by the energized relay. It should bestated, in passing, that when this armature switch is released it doesnot cause the engagement of the contacts 32 so that these contacts 32are engaged momentarily only once during a complete cycle of movement ofthe upper armature switch of relay 29. The circuit momentarilyestablished at the contacts 32 1s traceable from the grounded upperarmature switch of relay 29, the momentarily engaged contacts 32, thelower intermediate armature switch of the relay 33 and its normalcontact, the uppermost armature switch of sluggishly operating relay 34and its normal contact, the winding of the relay 34, an off normalswitch 35, the armature switch 0t relay 36 and its engaged contact, tothe grounded common battery 14. The relay 34,

eing now energized, establishes a locking circuit for itself traceablefrom the lowermost grounded armature switch of relay 33, the right handcontact of this armature switch, the upper intermediate armature switchof relay 34 and the contact then engaged thereby, the Winding of therelay, the of! normal switch 35, the armature swltch ofrelay 36 and itscontact, to the grounded battery 14. The lower intermediate armatureswitch of the relay 34 establishes a driving circuit traceable from thisarmature switch, which is grounded, the motor magnet 37, the sluggishlyoperating relay 38, the armature switch of relay 38 and its contact, the

side switch wiper 39 in its first position, to i the grounded commonbattery 14. The motor magnet 37 now sets the wipers 40, 41, 42, 43, and44 into movement until the wiper 43 engages an ungrounded waitingcontact whereupon the private magnet 45, whose circuit was closed uponthe initial energization of the motor magnet 37, has its circuit opened,the private magnet 45 thereupon causing the side switch wipers 39, 46,47 and 48 to move to their second positions, the side switch wiper 39 inmoving into its second position opening the circuit of the motor magnet37 to allow the wipers 40 to 44 inclusive to remain at rest.

The wipers 40 to 44, inclusive, form part of the selecting mechanismthat is employed to associate a' speech recording and reproducingmechanism with calling lines and these wipers are arrested inassociation with calling lines by the removal of ground from the waitingcontacts pertaining to the wiper 43, this removal of ground beingconsequent upon the energization .of relay 29 whose lower armatureswitch normally grounds waiting contacts of wipers 43 and ungroundsthese contacts for the purpose specified. Each link connector has arelay 29 individual thereto and the lower armature switch of each relay29 is individual to one contact for each wiper 43 of a plurality ofswitches G, the similarly positioned waiting contacts of the wipers ofthe switches G being in multiple connection. When all the switches G areidle the uppermost switch G is employed to the exclusion of the remaining switches and if this switch is busy the next succeeding switch Gis enabled to seek a calling line by the transfer of the connection fromthe contacts 32 to the lower intermediate armature switch of the relay33 of such succeeding switch G, this transfor being effected either byway of the alternate contact of the lower intermediate armature switchof the busy switch G or conjointly by way of the normal contact of thislower intermediate armature switch of such relay 33 and the alternatecontact of the upperlnost armature switch of relay 34. When the sideswitch wiper 48-is in its second position circuit is closed through therelay 30 by way of the wiper 42 and its then engaged contact. \Vhenrelay 30 is energized circuit of relay 29 is opened to releaseitsarmature switches, the lowermost armature switch of this relay 29 beingreleased to ground the associate waiting contacts of the Wipers 43 ofthe selector switches G to prevent other seeking switches G fromselecting the link connector E that has been se looted by a switch G.When the relay 30 is energized its armature switches engage theiralternate contacts to connect the wipers and 41 with the sides ofthecalling line and-'- these sides are extended into connection with theuppermost switches of the relay by way of the two upper armatureswitches of relay 33 and their then engaged contacts, the relay 33(referring of course to the employed selector switch G) being nowenergized owing to the location of the side switch wiper 39 in itssecond position.- W'hen the relay 33 is energized it opens the lockingcircuit for the relay 34 and the ground established by the lowerintermediate armature switch of relay 34 for relay 33 is replaced at theattracted left hand armature switch of relay 51 that is now in bridge ofthe calling line. The attracted right hand armature switch of relay 51establishes a circuit traceable from this switch, which is grounded, thecontact of the switch, the armature switch of relay 52, the normalcontact of this armature switch, the motor 53, to the grounded battery14. The motor 53 is thereupon set into operation to drive the wire orfiat band 54 of steel that enters into the formation of a well knownspeech recording and reproducing mechanism, this band serving to recordspeech and operating to reproduce speech as will appear. The band 54,which is now set into motion, travels between the poles of a recordingmagnet 55 that is in a closed local circuit with a secondary winding 56and a battery 57. The primary 58 to the coil 56 is in bridge of thecalling line by way of the two upper armature switches of the relay 50and their normal contacts. Any previous record impressed upon the tape54 is removed by the efi'acing magnet 59 between whose poles the tape 54moves, the tape traveling in a clockwise direction indicated by thearrow, the circuit for the erasing magnet 59 being closed by thelowermost armature switch of the relay 50.

The speech recording and reproducing mechanism is now in condition toreceive the record of the number desired by the calling subscriber andcontinuesv in operation gizing circuit momentarily established at.

the contact 60. It should be stated in passing that the motor 53 has agiven range of operation to cause the band 54 to travel through onecomplete cycle, this given range of operation being determined by thecontact finger 63 constituting a terminal of a circuit for the motor 53and which is included in this circuit during the rotation of the disk62, this circuit also including the grounded brush 64 in contact withthe disk 62. When the disk 62 has reached its normal position a portionof insulation carried thereby engages the contact finger 63 so as toopen the circuit of the motor 53 whereby the band 54 is brought to restafter this band has passed through one cycle. Simultaneously with theassociation of the speech recording magnet 55 with the callingsubscribers telephone equipment the selected A operators telephoneequipment H is also associated with the calling subscriber by way of thenormal contacts of the interme diate armature switch of relay 65. Thereselection of selected A operators squipment H is prevented by therelay 66 in bridge of the calling line whose lower armature switchestablishes circuit for the relay 67. Each A operators position has arelay 67 and this relay has as many armature switches as there are linkconnectors E pertaining to the position to which the relay 67 isindividual, the contact of each armature switch being individual to sucha link connector. The relay 67 is energized each time the relay 66(which is also common to the link connectors to which the relay 67 iscommon) is energized, the lowermost armature switch of the relay 31 of aselected link connector having its contact in connection with'thecontact of the armature switch of relay-67 individual to the selectedlink connector whereby the relay 67, when energized, is adapted to placeground upon the contact of the lowermost armature switch of relay 31 toprevent the selection of any unemployed links E in the group having therecalling subscriber of the number of the desired line may be delayeduntil the A operator requests such announcement.

When the calling subscriber announces the number of the line desiredsuch announcement is recorded upon the tape 54 by means of the recordingmagnet 55 that is now in telephonic connection with the callingsubscriberls telephone equipment. The selected A operators telephoneequipment H is at the same time in telephonic connection with thecalling subscribers telephone equipment and the selected A operator isenabled to hear the designation of the desired line at the same timethis designation is being recorded upon the tape 54. The selected Aoperator has no occasion to listen to anything more than the prefix tothe number of the desired line. For example, if the calling subscriberdesires Franklin 3436, the calling subscriber will speak thisdesignation which will 'be completely recorded upon the tape 54 but thereceiving operator A need pay no attention to the numerical portion ofthis designation since it will be the duty of the operator merely toconnect the calling line with the B operator at the exchange to whichthe called or desired line extends, the B operator listening to thenumerical portion of the designation of the desired line as reproducedby the selected-speech recording and reproducing device F. The Aoperator will insert the plug 5 of the selected link connector E intothe trunk jack 6 in order to ex tend the calling line to the exchange towhich the desired line also extends. In the embodiment of the inventionherein shown the jacks 6 are provided with tip and sleeve springs thatare engaged by the tip and sleeve contacts of the employed plug 5 andthe thimble that is engaged by the heel of the employed plug The tip andsleeve springs of each jack are connected with the two upper armatureswitches of a relay 68 and the winding of this relay is connected withthe thimble of the corresponding jack. \Vhen the plug is inserted thecircuit of relay 68 is established from the grounded terminal of therelay 68, the thimble of the employed jack 6. the heel of the employedplug 5, the relay 69, the relay to the grounded battery 14, whereuponthe relay 65 is energized. The intermediate armature switches of therelay 65 thereupon open the circuit of the relay 66 to release the relay67 and place the previously selected responsive device 'H in conditionto be selected by another calling subscriber. It should be stated, inpassing, that the signals 70 are individual to'the links E and enablethe A operators to determine which plug 5 has been selected. The groundremoved upon the denergization of the relay 67 is now replaced at thelowermost armature switch of relay 65 to jack 6 the lowermost armatureswitch of relay 68 establishes circuit for the sluggishly operatingrelay 72 and the motor magnet 73 by way of the side switch wiper 74 inits first position whereby the motor magnet 73 movesthe wipers 75, 76,and 77 until the wiper 77 engages an ungrounded waitingcontact whereuponthe private magnet 78, whose circuit was established upon the initialenergization of the motor magnet 73, has its circuit opened to bring theside switch wipers 74 and 79 to their second positions, the wiper 74opening the circuit of the motor magnet 73 to bring the wipers 75, 76and 77 to rest. The side switch wiper 74 in its second position closes acircuit through the relay 80, which circuit is apparent. The armatureswitches of relay 80 are thereupon attracted to extend the calling lineinto connection with the wipers 75 and 76 and the Wipers 75 and 76 areconnected with a connecting plug 7 by way of the contacts then engagedby said wipers. The relays 68 and 80, the wipers 75, 76, and 77, andassociate equipment may, if desired, be located at the A exchange whilethe conductors leading from the waiting contacts of the wipers 75, 76and 77 extend to the B exchange, certain jacks 6 being assigned to one Bexchange, others to another B exchange, etc., according to the number ofexchanges to which the calling subscribers are to have access by way ofA and B operators in the manner set forth. Thus each exchange having Boperators positions is provided with a group of jacks 6 and a group ofswitches K, each switch K having a jack 6 individual thereto. Similarlypositioned waiting contacts of the wipers 75, 76 and 77 of each suchgroup of switches K are in multiple connection, such multiple connectionbeing also desirably efi'ected at the A exchange.

The switch K pertaining to the exchange to which the desired lineextends having been arbitrarily selected by the selected A operator andset into operation until the wiper 77 engages an ungrounded contact, asdescribed, extends the calling line into connection with a connectingplug 7 which is located at some B operators position free to completethe desired connection, the conductors extending from the waitingcontacts of the wipers 75, 76 and 77 being distributed among the Boperators of a given exchange. The relay 81, each link L having such arelay, is now placed in bridge of the talking sides of its associatelink connector L that has been connected with the calling line, by

way of the normal contacts of the armature switches of relay 82, therelay 81 being thus included in serial relation with the calledsubscribers supervisory relay 83 and the difierential relay 84 as willbe apparent from an inspection of the diagrams. Relays 83 and 84 are nowincluded in circuit, but the relay 84 is not energized as it has twowindings that are equal and opposed. The intermediate armature switchesof the energized relay 81 include the selected B operators telephoneequipment 85 in telephonic relation with the talking sides of thecorresponding link connector L, there being equipment 86 performingfunctions similar to the equipment 67 to prevent any other switch K fromselecting the telephone equipment 85 while this telephone equipment isin selected condition. When relay 83 is operated its lower groundedarmature switch establishes a circuit which includes the lowermostarmature switch of relay 87 and its contact, the wiper 44 and itscontact, the side switch wiper 47 in its second position and the secondposition contact of this wiper, the relay 59 and the battery 14. Whenrelay 50 is energized-its two upper armature switches open the circuitof the primary or inducing winding 58 over which the calling subscriberpreviously talked and which serve to reimpress the calling subscribersvoice currents upon the secondary 56 to secure the designation of thedesired line upon the tape 54 so that no further record can, for thetime being, he. made upon said tape. The alternate contacts of these twoupper armature switches place the secondary coil 88 in bridge of thetelephone line extending from the calling station to the selected Boperators position. The lower armature switch of relay 50 opens thecircuit of the eifacing magnet 59. The lower intermediate armatureswitch of the relay 5O closes the circuit for the motor 53 to cause itto drive the tape 54 whereupon voice currents are induced in thereproducing magnet 89 by the recording magnetic fields in the tape 54.The reproducing magnet 89 is in circuit with the telephone receiver 90which is thus caused to have its diaphragm vibrated to produce soundwaves in conformity with the magnetic record upon the tape 54, thereceiver 90 thus operating to speak or repeat the designation of thedesired line recorded on the tape 54 by the calling subscriber throughthe aid of the primary or impressing coil 58, the secondary or inducedcoil 56, and the recording magnet 55. The receiver 90 speaks into atelephone transmitter 91 included in a primary circuit having aninducing coil 92 that is in inducing relation with the secondary coil88. As the coil 88 is now in bridge of the telephone line extendingbetween the calling station and the selected B operator, the designationof the desired line which is being reproduced will be heard both by thecalling subscriber and the selected B operator whereby the callingsubscriber has a check upon the number being repeated to the B operatorand whereby the B operator secures her instructions without any aid fromthe A operator or repetition by the calling subscriber. The motor 53 iscontinued in operation until the selected B operator has heard thedesignation of the desired line to her satisfaction whereafter such Bvoperator inserts the selected plug 7 into the jack of the desired line,the heel of this plug and the thimble of this jack closing a circuit forthe relay 93 and the relay 82. When relay 82 is energized its armatureswitches are attracted to open the circuit of relay 81. The circuit ofthe sluggishly operating relay 94 which was previously closed at thetopmost switch of relay 81 is now deenergized but this armature switchremains in its attracted position a certain length of time to establisha circuit for the topmost and grounded armature switch of relay 81, thenormal contact of this switch, the armature switch of relay 94 and itscontact, the upper side of the selected link connector L, thence byobvious connections to the upper windings of relays 83 and 84 whereuponthe coils of the relay 84 are unbalanced momentarily to bring thegrounded armature switch of relay 84 into connection with its contact tooperate and establish a locking circuit for the relay 87, this lockingcircuit being apparent. When relay 87 is energized it obviouslyestablishes a circuit for the relay 31. When the relay 31 is energizedits intermediate armature switches open the circuit of the relay 51 thatwas previously in bridge of the calling line. The left hand armatureswitch of relay 51 thereupon opens the circuit of the associate relay33. The lowermost armature switch of relay 33, which switch is ground--ed, establishes a circuit, by way of its left hand contact, through therelease magnet 36 and the previously closed off normal switch 95 torestore the previously employed selector switch G to normal, it beingmentioned in passing, that the ofi' normal switch 35 is only openedwhen'the wipers 41, 42, 43 and pass beyond their normal range ofoperation to cause the relay 34 to be released and thus establishcircuit for the release magnet 36 to restore the switch to normal. Theswitch 35 is provided only to take care of an emergency that'mightoccasion the improper operation of a switch G, such an emergency beingextremely rare. Gircuit for the relay 50 is now opened at the sideswitch wiper 47 when restored to its first position thereby opening thecircuit for the motor 53 at the lower intermediate armature switch ofthe relay 50, the motor continuing in operation until the contact 63engages the insulation upon the disk 62. The equipment of the previouslyemployed selector switch G and the previously selected talking device Fare now restored to normal.

The selected B operator may test the called line by means of anydesirable equipment before inserting the plug 7 in the jack of a calledline and if the desired line is tested idle the signal bell at thedesired station may be operated in any suitable way as by means of aringing key 96. The called subscriber governs the supervisory relay 97whose lower armature switch controls the left and low resistance windingof the relay 98, the right hand winding of the relay 98 being of highresistance to prevent relay 83 from operating through it whereby the Aoperator is given complete control of the connection between the callingand called lines, the B operator not taking down her portion of theconnection until the A operator withdraws her plug 5, the withdrawal ofthis plug 5 occasioning the operation of the supervisory signal 99 atthe B operators position, the circuit of the right hand winding 98 beingdependent upon the plug 5 and the jack 6 holding the same. That is therelay 98 is denergized by the removal of such plug 5 to occasion theoperation of the signal 99 and the B operator takes down her portion ofthe connection in response to the signal displayed by the signal device99.

The A operator takes down her portion of the connection in response tothe signal displayed to her by the supervisory signals 100 and 101,signal 100 being controlled by the calling subscriber and signal 101being controlled by the called subscriber. When plug 5 is removed fromthe jack by the A operator the relay 65 is deenergized, the lowermostand grounded armature switch of this relay then opening the circuit ofthe relay 16 to restore the calling line equipment to normal, thelowermost and grounded armature switch of relay 16 establishing circuitthrough the release magnet 102 and the previously closed off normalswitch 103 to cause the side switch wipers 20, 26 and 27, the wipers 21,22, 23 and 24 to restore to normal. When the plug 5 was removed from itsjack 6 the circuit of relay 68 was opened, the lowermost and groundedarmature switch of this relay 68 establishing a circuit for the releasemagnet 104 and the previously closed off normal switch 105 whereby thewipers 74, 75, 76, 77 and 79 are restored to normal. lVhen the Boperator has taken down her portion of the connection the heel of theconnecting plug 7 is removed from the circuit which it previouslyestablished through the relays 93 and 82 to deenergize these relays andcause the final restoration of the equlipment of the selected B operatorto norma While I have herein shown and particularly described thepreferred embodiment of my invention I do not Wish to be limlted to theprecise details of construction and circuit arrangement shown as changesmay readily be made without departing from the spirit of the invention.

Having thus described my invention I claim as new and desire to secureby Letters Patent the following 1. A telephone exchange system includingtelephone lines extending to call receiving and switching or connectingoperators positions and divided into groups for accessibility by thelatter operators, there being a plurality of switching operatorspositions for each group of telephone lines; speech recording and recordreproducing apparatus operable by calling subscribers for re cordingtheir speech; switching mechanism whereby a speech-recording portion isconnected with a calling line; and switching means governed by areceiving operator for bringing the, speech reproducing portion of saidapparatus interchangeably into connection with the switching orconnecting operators positions, said means including selector switchesfor selecting an idle operator in the group of positions containingwanted mes.

2'. A telephone exchange system including telephone lines extending tocall receivmg and switching or connecting operators positions anddivlded into groups for accessibility by the latter operators, therebeing a plurality of switching operators positions for each group oftelephone lines; speech recording and record reproducing apparatusoperable by calling subscribers for record ing their speech; switchingmechanism whereby a speech-recording portion is connected with a callingline; link connectors for extending calllng lines and interchangeablyassociated with the switching or connectlng operators positions by areceiving operator and serving to convey the record reproductions to theselected switching operator; and selector switches for selecting an idleoperator in the group of positlons having access to wanted lines.

3. A telephone exchange system includng telephone lines extending tocall receiving and switching or connecting operators positions anddivided into groups for accessibility by the latter operators, therebeing a plurality of switching operators positions for each group oftelephone lines; speech recording and record reproducing devicesoperable by calling subscribers for recording their speech; switchingmechanism whereby a speech-recording portion is connected with a callingline; link connectors for extending calling lines and'interchangeablyassociated with the switching or connectlng operators positions by areceiving operator and serving'to convey the 1 speech recording andrecord reproducing record reproductions to the selected switching 0erator; selector switches for connecting t e reproducing portions ofspeech re cording and record reproducing devices with said linkconnectors; and selector switches for selecting an idle operator in thegroup of positions having access to wanted lines.

4. A telephone exchange system including telephone lines extending tocall receiving and switching or connecting operators positions anddivided into groups for ac cessibility by the latter operators, therebeing a plurality of switching operators positions for each group oftelephone lines;

devices operable by calling subscribers for recording their speech; linkconnectors for extending calling lines and interchangeably associatedwith the switching or connecting operators positions by a receivingoperator and serving to convey the record reproductions to the selectedswitching operator; selector switches for connecting the reproducingportions of speech recording and record reproducing devices with saidlink connectors; and selector switches for selecting an idle operator inthe group of positions having access to wanted lines and for connectingthe speech recording portions of said devices with calling lines.

5. A telephone exchange system including telephone lines extendingtocall receiving and switching or connecting operators positions anddivided into groups for accessibility by the latter operators, therebeing a plurality of switching operators positions for each group oftelephone lines; speech recording and record reproducing devicesoperable by calling subscribers for recording their speech; meansgoverned by a receiving operator for bringing the speech reproducingportion of said devices interchangeably into connection with theswitching or connecting operators positions, said means includingselector switches for selecting an idle operator in the group ofpositions containing wanted lines; and selector switches for connectingthe speech recording positions of the s eech recording irnd recordreproducing devlces with calling mes.

6. A. telephone exchange system including telephone lines extending tocall receiving and switching or connecting operators positions anddivided into groups for accessibility by the latter operators; linkconnectors employed by a receiving operator for extending calling lines;speech recording and record reproducing apparatus operable by callingsubscribers for recording their speech; automatically operating callingsubscriber-controlled selecting switching mechanism for coupling thespeech recording portion of said apparatus with a calling line and forcoupling the speech reproducing portion with a link connector; andswitching mechanism governed by a receiving operator for bringing anemployed'link connector and the speech reproducing portion coupledtherewith interchangeably into connection with the switching orconnecting opby calling subscribers for recording their speech;automatically operating selecting switching mechanism for coupling thespeech recording portion of said apparatus with a calling line and forcoupling the speech reproducing portion with a link connector; andswitching mechanism governed by a receiving operator for bringing anemployed link connector and the speech reproducing portion coupledtherewith interchangeably into connection with the switching orconnecting operators positions.

8. A telephone exchange system including telephone lines extending tocall receiving and switching or connecting operators positions anddivided into groups for accessibility by the latter operators; linkconnectors employed by a receiving operator for extending calling lines;speech recording and record reproducing apparatus operable by callingsubscribers for recording their speech; switching mechanism forconnecting the speech recording portion of said apparatus with a callingline; automatically operating calling subscriber controlled selectingswitching mechanism for coupling the speech reproducing portion of saidapparatus with an employed link connector; and switching mechanismgoverned by a receiving operator for bringing an employed link connectorand the speech reproducing portion coupled therewith interchangeablyinto connection with the switching or connecting operators positions.

9. A telephone exchange system including telephone lines extending tocall receiving and switching or connecting operators positions anddivided into groups for accessibility by the latter operators; linkconnectors employed by a receiving operator for extending calling lines;speech recording and record reproducing apparatus operable by callingsubscribers for recording their speech; switching mechanism forconnecting the speech recording portion of said apparatus with a callingline; automatically operating selecting switching mechanism for couplingthe speech reproducing portion of said apparatus with an employed linkconnector; and switching mechanism governed by a receiving operator forbringing an employed link connector and the speech reproducing portioncoupled therewith interchangeably into connection with the switching orconnecting operators positions.

10. A telephone exchange system including telephone lines extending tocall receiving and switching or connecting operators positions anddivided into groups for accessibility by the latter operators; linkconnectors employed by a receiving operator for extending calling lines;speech recording and record reproducing apparatus operable by callingsubscribers for recording their speech; switching mechanism forconnecting the speech recording portion of said apparatus with a callingline; switching mechanism for interchangeably connecting the speechreproducing portion of said apparatus with the link connectors; andswitching mechanism governed by a receiving operator for bringing anemployed link connector and the speech reproducing portion coupledtherewith interchangeably into connection with the switching orconnecting operators positions.

In witness whereof, I hereunto subscribe my name this 21st day ofFebruary, A. D.

MORTON L. JOHNSON. Witnesses:

G. L. CRAGG, ETTA L. WHITE.

